1. Field of the Invention
The present invention relates to recording apparatuses for forming images on recording sheets, such as, for example, photocopiers, printers, facsimile apparatuses, and so forth.
2. Description of the Related Art
With regard to conventional recording apparatuses, ink-jet recording apparatuses, for example, have been configured based on a chassis that has integral side plates. The configuration of a conventional ink-jet recording apparatus will be described with reference to FIG. 12.
In FIG. 12, reference numeral 101 denotes a recording head, and 102 denotes a carriage for mounting the recording head 101. Reference numeral 104 is a guide shaft which serves as a guiding member for guiding the motion of the carriage 102 in the directions indicated by the arrow A in the figure, which are the main scanning directions, and 105 denotes a guide rail which is another guiding member for guiding the movement of the carriage 102. Reference numeral 106 denotes a timing belt wound around two pulleys (only one pulley 107 shown in the figure), with part of the timing belt 106 being fixed to the carriage 102.
The pulley 107 is directly linked to a carriage motor M1, enabling the carriage 102 carrying the recording head 101 to be scanned in the directions indicated by the arrow A by driving the carriage motor M1. Reference numeral 108 denotes a scale for indicating the absolute position in the scanning direction of the carriage 102, and 113 denotes a recovery unit for performing discharge recovery processing of the recording head 101.
Reference numeral 114 denotes a transporting roller driven by a transporting motor M2 to transport recording sheets. Reference numeral 115 denotes a pinch roller for abutting the recording sheet against the transporting roller 114 with a spring (not shown), and 116 denotes a pinch roller holder for rotatably supporting the pinch roller 115. Reference numeral 117 denotes a transporting roller gear fixed to one end of the transporting roller 114. The transporting roller 114 is driven by the motive force of the transporting motor M2 being transmitted to the transmitting roller gear 117 via an intermediate gear 118.
Reference numeral 119 denotes a discharging roller gear fixed to a discharging roller (not shown) for discharging recording sheets, upon which images have been formed by the recording head 101, outside of the recording apparatus, wherein the motive force of the transporting motor M2 is transmitted to the discharging roller gear 119 via the intermediate gear 118. Reference numeral 120 denotes an automatic sheet feeding device for loading multiple recording sheets thereupon, and separating and feeding the sheets one at a time.
Next, description will be made regarding the configuration of the chassis.
A pulley (not shown) is rotatably fixed on a main face 109A of the chassis 109, on the side opposite from the carriage motor M1, and the pulley 107. A left side face 109C is configured to be bent from the main face 109A, and the guide shaft 104, scale 108, and transporting motor M2 are positioned and fixed thereto. Also, the transporting roller 114 and discharging roller (not shown) are rotatably positioned and fixed by bearings (not shown).
A right side face 109B opposite to left side face 109C, also is configured to be bent away from the main face 109A, and the guide shaft 104 and scale 108 are positioned and fixed thereto. Also, a middle side face 109D also is configured to be bent away from the main face 109A, and the transporting roller 114 and the discharging roller (not shown) are rotatably positioned and fixed by bearings (not shown). The side faces 109B, 109C, and 109D are linked and fixed by being screwed to a separate linking chassis 141, thereby exhibiting precision and rigidity.
The recovery unit 113 is positioned and fixed to the main face 109A, right side face 109B, and middle side face 109D. Also, a first sheet guide member (not shown) for guiding recording sheets fed from the automatic sheet feeding device 120 to the nipping portion between the transporting roller 114 and pinch roller 115, a platen 128 which is a second sheet guiding member for holding recording sheets between the transporting roller 114 and the discharging roller (not shown), and a third sheet guiding member (not shown) for holding the recording sheets at the time of discharging the recording sheets from the discharging roller out from the main unit, are positioned and fixed to the left side plate 109C and the middle side plate 109D.
However, there have been the following problems with conventional recording apparatuses.
With conventional recording apparatuses, the sheet guide member becomes long in the width direction of the recording medium, which raises costs. Also, there has been a problem that the dimensions of the sheet guide member differ at positions close to the attachment parts of the side plates 109C and 109D as compared to that at the center part, due to bowing of the sheet guide member in the width direction. These are not currently problematic, but in the event that images are to be recorded with higher precision than what is currently being performed, there is the possibility that sheet transporting may be unstable, or the distance between the recording head and the recording face of the recording sheet may not be uniform, to a point of not being negligible.
As measures against these problems, increasing the precision of the dimensions for preventing bowing of the sheet guide member has been proposed, but there is a limit to how far precision can be improved, and also increased precision further increases costs. Another proposed arrangement involves forming another side plate by bending from the main face 109A between the left side plate 109C and middle side plate 109D. This configuration has been effective against bowing by reducing the width-wise direction of the sheet guide member, but the effects of bowing of the sheet guide member between the side plates still remain, and the problem was not solved by this arrangement.
Also, another proposed arrangement involves positioning the sheet guide member relative to the transporting roller 114 and the discharging roller (not shown). This is a good configuration from the perspective of precisely positioning the sheet guide member in the width direction by configuring positioning parts at multiple positions in the width direction for the sheet guide member relative to a transporting roller and discharging roller with high rigidity and straightness, but in order to configure a positioning part at the transporting area of the recording sheet, there has been a need to form an outer circumference part smaller than the outer circumference of the transporting roller 114 (i.e., the recording sheet transporting face) and configure a positioning part there. In the event that the transporting roller 114 is a metal roller, this requires a grinding process for configuring the portion with a smaller outer circumference, which leads to great increases in costs for forming the roller. Also, the rigidity decreases, which leads to a problem in that the transporting roller 114 arches more readily.
Also, another problem is that, in shipping, the required space for the chassis 109 is great since the chassis 109 comprises side plates 109B, 109C, and 109D, bent from the main face 109A, so the packing efficiency is poor, leading to increased transporting and handling management costs. Also, the edges of the side plates 109B, 109C, and 109D are long and unstable, so other members are necessary for protecting these parts, further increasing costs.
Also, the positions of the side plates 109B, 109C, and 109D relative to the main face 109A, and the relative positions of the side plates 109B, 109C, and 109D amongst themselves are determined by precision in the bending process, so there has been the problem that high precision is not readily attained, leading to problems such as low yield and increased costs in working machinery for increasing precision, and so forth.
Also, as another problem, linking the chassis 109 and linkage chassis 141 by the side plates 109B, 109C, and 109D generates rigidity of the overall chassis, but the side plates 109B, 109C, and 109D are formed by bending portions of the main face 109A, so while the rigidity is high in the event that a sufficient bending range is obtained, rigidity deteriorates in the event that sufficient bending range cannot be obtained, as with the middle side plate 109D. Also, the bent portions of side plates 109B and 109c may be reduced in the event that attaching portions for parts need to be formed around the bent portions, leading to a problem that further supporting members are required.
Also, as yet another problem, plates 109A, 109B, 109C, and 109D are integrally formed, so the chassis 109 must be redesigned to alter the length of the main face 109A for products in which the sheet width is different. Also, the chassis 109 must be redesigned for products in which the driving system for transporting is different, and products in which the form of the side faces 109B and 109C is modified due to changes in the main scanning system. Accordingly, there has been a need for reduction in the cost of parts, assembly, and management, with regard to standardization of parts between models, and making a series of products, and handling improved versions of products, etc., has been difficult.
The present invention provides a recording apparatus capable of realizing improved precision and rigidity of the chassis configuration, and standardization of parts between models, at low cost.
To this end, a recording apparatus for recording on a recording medium with a recording head, comprises: a base chassis; transporting means for transporting the recording medium; head mounting means for mounting the recording head; holding means for holding the head mounting means; two side plates connected to opposite ends of the base chassis across a transporting path for transporting the recording medium; first positioning parts, disposed on a predetermined face of each of the two side plates, for positioning the side plates on the base chassis; second positioning parts, disposed on the predetermined face of each of the two side plates, for positioning the holding means on the side plates; and a third positioning part, disposed on one of the two side plates, for positioning the transporting means on at least one of the side plates.
Further objects, features and advantages of the present invention will become apparent from the following description of the preferred embodiments (with reference to the attached drawings).